JP5794381B2 - Travel control device and travel control method - Google Patents

Description

  The present invention relates to a travel control device and a travel control method.

2. Description of the Related Art A technique for detecting an obstacle approaching the periphery of a vehicle using an obstacle sensor mounted on the vehicle is conventionally known (see, for example, Patent Document 1).
Japanese Patent Application Laid-Open No. H10-260260 detects shooting of an obstacle by a camera mounted on a vehicle, triggered by the detection of an obstacle by an ultrasonic sensor in order to detect and record a weak impact or theft at the time of parking and stopping. Video recording has started.

JP 2009-280109 A

  However, in Patent Document 1, when it is determined that the obstacle detected by the ultrasonic sensor is within a preset distance, only shooting of the obstacle and recording of the video by the camera mounted on the vehicle is started. . For this reason, the danger level of the detected obstacle cannot be notified to the driver.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a travel control that changes the warning timing according to the danger level of an obstacle and notifies the driver of the danger level of the obstacle. An apparatus and a traveling control method are provided.

The travel control apparatus according to the first aspect of the present invention includes an ultrasonic obstacle detection unit, an image acquisition unit, an image obstacle detection unit, a backward movement preparation detection unit, a warning unit, and a warning control unit. And a threshold control unit. The ultrasonic obstacle detection unit detects an obstacle approaching the rear of the host vehicle and a distance from the obstacle using ultrasonic waves. An image acquisition part acquires the image of the range including the back of the own vehicle. The image obstacle detection unit detects an obstacle approaching the rear of the host vehicle using the image acquired by the image acquisition unit. The backward movement preparation detection unit detects that the own vehicle is moving backward by detecting that the shift position of the transmission of the own vehicle is the reverse position . The warning unit warns the driver of the host vehicle about the obstacle detected by the ultrasonic obstacle detection unit. The warning control unit controls the warning unit to issue a warning when the distance from the obstacle detected by the ultrasonic obstacle detection unit is equal to or less than a warning threshold value. The threshold control unit is configured such that the vehicle speed of the host vehicle is high except when the backward movement preparation detection unit detects that the host vehicle is preparing to move backward, and the image obstacle detection unit detects an obstacle. The operation threshold value is controlled in accordance with the speed of the host vehicle so that the operation threshold value increases as the time increases. When the preparation for moving the vehicle backward is detected by the backward movement detection detection unit and the image obstacle detection unit detects an obstacle, the threshold control unit sets the operation threshold to the vehicle speed of the vehicle. The operation threshold value is controlled to a constant value regardless of the speed of the host vehicle so that a warning is more easily performed than in the case where the control is performed accordingly.

The travel control method according to the second aspect of the present invention includes the ultrasonic obstacle detection unit, the image acquisition unit, the image obstacle detection unit, the backward movement preparation detection unit, and the warning unit. A travel control method using a travel control device, wherein the warning unit is controlled so that a warning is issued when the distance from the obstacle detected by the ultrasonic obstacle detection unit is equal to or less than a warning threshold value. The threshold of operation increases as the vehicle speed increases except when the backward movement preparation detection unit detects the preparation of the vehicle moving backward and the image obstacle detection unit detects an obstacle. The operation threshold is controlled in accordance with the speed of the vehicle so that the preparation for the vehicle to move backward is detected by the backward movement detection detection unit, and the image obstacle detection unit detects the obstacle. If the operating threshold is controlled according to the vehicle speed Warned is easily performed Te, to control the operation threshold at a constant value regardless of the vehicle speed of the vehicle.

FIG. 1 is a schematic diagram illustrating a vehicle layout example of a travel control device according to an embodiment. FIG. 2 is a block diagram illustrating a configuration of the travel control apparatus according to the embodiment. FIG. 3 is a block diagram showing a specific configuration example of the host vehicle information acquisition unit 21 of FIG. FIG. 4 is a block diagram illustrating a specific configuration example of the peripheral information acquisition unit 22 of FIG. FIG. 5 is a block diagram illustrating a specific configuration example of the control determination information calculation unit 24 of FIG. FIG. 6 is a plan view illustrating ultrasonic detection ranges CRL, CNL, CNR, and CRR in which the ultrasonic obstacle detection sensors 13e to 13h can detect an obstacle. FIG. 7 is a plan view showing detection angle regions GDL, GDC1, GDC2, and GDR in which the image obstacle detection unit 44 can detect an obstacle. FIG. 8 is a graph showing an example of the relationship between the first threshold value SV1 to the fourth threshold value SV4 calculated by the first threshold value calculation unit 48 to the fourth threshold value calculation unit 51 and the host vehicle speed. is there. FIG. 9 is a plan view showing a case where the image obstacle detection unit 44 detects an obstacle OBJ in the left side detection angle region GDL. FIG. 10 is a plan view showing a case where the image obstacle detection unit 44 detects an obstacle OBJ in the rear detection angle region GDC1 or GDC2. FIG. 11 is a plan view showing a case where the image obstacle detection unit 44 detects an obstacle OBJ in the left side detection angle region GDL and detects an obstacle OBJ in the rear detection angle region GDC1 within a predetermined time. FIG. 12 is a flowchart illustrating the operation of the travel control device when executing the travel control process. FIG. 13A is a graph showing an example of the operating threshold value SSV and the distance DOD with the obstacles detected by the ultrasonic obstacle detection sensors 13e to 13h, which change with the passage of time. ) Is a graph showing an example of an obstacle detection state by the image obstacle detection unit 44, and FIG. 13C is a graph showing an example of an obstacle approach warning determination state by the warning unit.

  Embodiments of the present invention will be described below with reference to the drawings. In the description of the drawings, the same parts are denoted by the same reference numerals.

[Running control device]
With reference to FIG. 1, an example of a vehicle layout of the travel control apparatus according to the embodiment will be described. The vehicle 1 (hereinafter referred to as “own vehicle”) includes brake lamps 4a and 4b, an ignition switch 18 for instructing start and stop of a driving force generator including an engine and a motor, and an obstacle approaching the front PD of the own vehicle 1. Front obstacle detection sensors 13a to 13d, 19e for detecting an obstacle, obstacles approaching the rear of the vehicle 1, and a plurality of ultrasonic obstacle detection units that detect the distance from the obstacle using ultrasonic waves Sonic obstacle detection sensors 13e to 13h, a camera 46 (image acquisition unit) for acquiring an image in a range including the rear of the own vehicle 1, a driving force generating device 36 for generating driving force of the own vehicle, a braking force generating device 27, An accelerator pedal reaction force generator 30, a notification device 33 that notifies the driver of the approach of an obstacle, and a vehicle control device 2 that controls the entire vehicle 1 are mounted.

  The front obstacle detection sensors 13a to 13d are provided, for example, in a front bumper of the own vehicle 1, and the ultrasonic obstacle detection sensors 13e to 13h and the camera 46 are provided, for example, in a rear bumper of the own vehicle 1. As the front obstacle detection sensors 13a to 13d and the ultrasonic obstacle detection sensors 13e to 13h, a sonar that detects the distance from the obstacle and the obstacle that enters a relatively near area from the own vehicle 1 using ultrasonic waves. A detector can be used. The front obstacle detection sensor 19e is provided in a front bumper of the host vehicle 1, for example. As the front obstacle detection sensor 19e, a radar detector that detects an obstacle that enters an area relatively far from the vehicle 1 using electromagnetic waves can be used. The vehicle control device 2 is configured by an arithmetic processing device such as an ECU (Engine Control Unit), and the operation of the entire vehicle 1 is controlled by a CPU in the arithmetic processing device executing a computer program stored in advance.

  With reference to FIG. 2, the structure of the traveling control apparatus concerning embodiment is demonstrated. The travel control device according to the embodiment includes a host vehicle information acquisition unit 21 that acquires information of the host vehicle 1, a peripheral information acquisition unit 22 that acquires information about the periphery of the host vehicle, a system state selection unit 23, and control determination information. A calculation unit 24 and a warning device that issues a warning to an obstacle detected by the surrounding information acquisition unit 22 are provided. Here, the warning device includes a braking force generation system (25 to 27) that generates a braking force as an obstacle approach warning, and an accelerator pedal operation reaction force that generates an accelerator pedal operation reaction force as an obstacle approach warning. A system (28 to 30), a notification system (31 to 33) that issues a warning to the driver as an obstacle approach warning, and a driving force control system (34 to 36) that performs a driving force control as an obstacle approach warning Is included.

  As shown in FIG. 3, the host vehicle information acquisition unit 21 detects wheel speed sensors 11 a to 11 d installed on the wheels 20 a to 20 d of the host vehicle 1 and accelerator opening detection installed on the accelerator pedal of the host vehicle 1. Part 5, a brake pedal position detector 6 that detects the position of the brake pedal of the vehicle 1, a shift position detector 9 (rear movement preparation detector) that detects the shift position of the vehicle 1, and a travel control device The SW operation recognition unit 3 that detects the state of the on / off switch, the steering sensor 10 that detects the steering angle of the steering of the host vehicle 1, and the acceleration / deceleration sensor 12 that detects the acceleration / deceleration of the host vehicle 1 are provided. .

  The wheel speed sensors 11a to 11d detect the rotational speeds of the wheels 20a to 20d of the host vehicle 1, respectively. The own vehicle speed calculation unit 40 calculates the own vehicle speed (wheel speed) from the respective rotation speeds of the wheels 20a to 20d in consideration of the rotation radius of the wheels 20a to 20d. Further, the host vehicle speed calculation unit 40 calculates the travel distance by integrating the host vehicle speed. The brake pedal position detector 6 detects whether or not the driver is depressing the brake pedal and the amount of depression of the brake pedal. The shift position detector 9 detects the state of the shift position in order to detect the current state of the transmission. An example of detecting that the vehicle 1 is ready to move backward includes that the shift position detection unit 9 detects a reverse (R) position. The SW operation recognition unit 3 detects the switch state of the travel control device and the switch state of the ignition switch 18. The steering angle calculation unit 41 performs a filtering process on the steering angle of the steering detected by the steering sensor 10 as necessary. The acceleration / deceleration calculation unit 42 performs filter processing on the acceleration / deceleration of the host vehicle 1 detected by the acceleration / deceleration sensor 12 as necessary. The own vehicle information output unit 43 determines the vehicle speed of the own vehicle 1, the accelerator opening, the position of the brake pedal, the shift position, the state of the on / off switch of the travel control device, the steering angle and the acceleration / deceleration. The information is transferred to the system state selection unit 23 or the control determination information calculation unit 24. The own vehicle speed calculation unit 40, the steer angle calculation unit 41, the acceleration / deceleration calculation unit 42, and the own vehicle information output unit 43 can be configured as a part of the vehicle control device 2 of FIG. Of course, an arithmetic processing device different from the vehicle control device 2 is prepared, and a CPU in the arithmetic processing device executes a computer program stored in advance. Thereby, you may implement | achieve operation | movement of the own vehicle speed calculating part 40, the steering angle calculating part 41, the acceleration / deceleration calculating part 42, and the own vehicle information output part 43.

A detailed configuration example of the peripheral information acquisition unit 22 will be described with reference to FIG. The peripheral information acquisition unit 22 includes at least the ultrasonic obstacle detection sensors 13e to 13h and a camera 46 (image acquisition unit) that acquires an image in a range including the rear of the host vehicle 1. The relative distance calculation unit 39 performs a filtering process on the value of the distance from the obstacle detected by the ultrasonic obstacle detection sensors 13e to 13h as necessary. The relative speed estimation unit 38 estimates the relative speed with the obstacle from the distance to the obstacle. The sign of the relative speed is positive when the obstacle approaches the host vehicle 1 and negative when the obstacle moves away. Furthermore, the relative speed estimation unit 38 calculates the time (approach time) required for the obstacle to approach the host vehicle 1 from the distance and relative speed with the obstacle detected by the ultrasonic obstacle detection sensors 13e to 13h. calculate. The approach time may be, for example, TTC (collision time) obtained by dividing the distance from the obstacle by the relative speed. The image obstacle detection unit 44 detects an obstacle approaching the rear of the host vehicle 1 and the distance from the obstacle using an image acquired by the camera 46. Although not shown, the peripheral information acquisition unit 22, In addition, the arithmetic processing apparatus for processing a sensing result by the front obstacle detection sensor 13 a to 13 d, 19e placed at the front of the vehicle 1 shown in FIG. 1 Is provided. The surrounding information output unit 45 uses the front PD of the vehicle 1 and the presence or absence of obstacles behind, the distance and relative speed with the obstacle, the approach time, and the detection direction or angle of the obstacle described later as the surrounding information. Then, the data is transferred to the system state selection unit 23 or the control determination information calculation unit 24. The relative distance calculation unit 39, the relative speed estimation unit 38, the image obstacle detection unit 44, and the peripheral information output unit 45 can be configured as a part of the vehicle control device 2 in FIG. Of course, an arithmetic processing device different from the vehicle control device 2 is prepared, and a CPU in the arithmetic processing device executes a computer program stored in advance. Accordingly, the operations of the relative distance calculation unit 39, the relative speed estimation unit 38, the image obstacle detection unit 44, and the peripheral information output unit 45 may be realized.

  The system state selection unit 23 determines whether to turn the system state on or off based on the state of the on / off switch of the travel control device detected by the SW operation recognition unit 3.

  With reference to FIG. 6, the ultrasonic detection ranges CRL, CNL, CNR, and CRR that the ultrasonic obstacle detection sensors 13e to 13h can detect an obstacle will be described. The ultrasonic obstacle detection sensors 13e to 13h as the ultrasonic obstacle detection unit include at least sensors 13f and 13g installed in the central portion in the rear portion of the own vehicle 1 and sensors installed in the left portion in the rear portion of the own vehicle 1. 13e and a sensor 13h installed on the right side of the rear of the host vehicle 1. In the embodiment, a case where two ultrasonic obstacle detection sensors 13f and 13g are installed in the central portion is shown, but only one may be used.

  The ultrasonic obstacle detection sensors 13e to 13h can detect the distances between the obstacles entering the ultrasonic detection ranges CRL, CNL, CNR, and CRR extending from the rear bumper of the vehicle 1 to the rear and the obstacles, respectively. it can. The ultrasonic detection ranges CNL and CNR are formed in a region including the central portion in the rear part of the own vehicle 1, and the ultrasonic detection ranges CRL and CRR are formed in regions adjacent to both sides of the ultrasonic detection ranges CNL and CNR, respectively. Yes. The ultrasonic obstacle detection sensors 13e to 13h and the ultrasonic detection ranges CRL, CNL, CNR, and CRR have a one-to-one correspondence. The adjacent ultrasonic detection ranges CRL, CNL, CNR, and CRR partially overlap each other.

  With reference to FIG. 7, detection angle regions GDL, GDC1, GDC2, and GDR in which an obstacle can be detected using the camera 46 will be described. The detection angle regions GDL, GDC1, GDC2, and GDR are regions in which the image obstacle detection unit 44 can detect an obstacle using an image captured by the camera 46. The image obstacle detection unit 44 divides a range including the rear of the host vehicle 1 into a plurality of detection angle regions GDL, GDC1, GDC2, and GDR, and the obstacle entering the rear of the host vehicle 1 is based on the edge information of the image. Thus, detection is performed for each detection angle region. That is, the image obstacle detection unit 44 can specify an obstacle that enters the rear of the host vehicle 1, a distance from the obstacle, and detection angle regions GDL, GDC1, GDC2, and GDR where the obstacle has entered.

  The image obstacle detection unit 44 includes at least a rear detection angle region (GDC1, GDC2) including the rear of the host vehicle 1 as a plurality of detection angle regions, and a left side detection angle region GDL adjacent to both sides of the rear detection angle region. And the right detection angle region GDR. In the embodiment, a case where the rear detection angle region including the rear of the host vehicle 1 is further divided into two regions GDC1 and GDC2 will be described, but the two regions GDC1 and GDC2 may not be divided.

  A specific configuration example of the control determination information calculation unit 24 of FIG. 2 will be described with reference to FIG. The control determination information calculation unit 24 includes a first threshold value calculation unit 48 that calculates a first threshold value that is a warning determination criterion, and a second threshold value that calculates a second threshold value that is a warning determination criterion. A value calculation unit 49, a third threshold value calculation unit 50 that calculates a third threshold value that is a warning criterion, and a fourth threshold value calculation that calculates a fourth threshold value that is a warning criterion Unit 51 and a threshold value setting unit 52 (threshold value control unit) for selecting an operation threshold value from the first threshold value to the fourth threshold value. The operation threshold value selected by the threshold setting unit 52 is transmitted to the braking control determination unit 25, the accelerator pedal operation reaction force determination unit 28, the notification determination unit 31, and the driving force control determination unit 34, respectively.

  As shown in FIG. 8, the first threshold value SV1 calculated by the first threshold value calculation unit 48 changes according to the host vehicle speed. Specifically, the first threshold value SV1 increases as the vehicle speed of the host vehicle 1 increases. When the host vehicle speed is 0, the vehicle speed may be offset to take a predetermined value. The first threshold value calculation unit 48 calculates the first threshold value SV1 for each of the ultrasonic obstacle detection sensors 13e to 13h. Further, the first threshold value calculation unit 48 may change the first threshold value SV1 according to the approach time calculated by the relative speed estimation unit 38. Further, the first threshold value calculation unit 48 may change the first threshold value SV1 based on the acceleration of the host vehicle 1 detected by the acceleration / deceleration sensor 12 or the steering angle detected by the steering sensor 10. Good.

  When the image obstacle detecting unit 44 detects an obstacle approaching the rear of the host vehicle 1, the second threshold value calculating unit 49 does not depend on the host vehicle speed as shown in FIG. A constant value SV2 (for example, 1.5 m) is calculated. The second threshold value calculation unit 49 sets the second threshold value to 0 when the image obstacle detection unit 44 has not detected an obstacle approaching the rear of the host vehicle 1.

  When the image obstacle detecting unit 44 detects an obstacle approaching the rear of the host vehicle 1, the third threshold value calculating unit 50 does not depend on the host vehicle speed as shown in FIG. A constant value SV3 (for example, 1.0 m) is calculated. The third threshold value calculation unit 50 sets the third threshold value to 0 when the image obstacle detection unit 44 has not detected an obstacle approaching the rear of the host vehicle 1.

  When the image obstacle detection unit 44 detects an obstacle approaching the rear of the vehicle 1, the fourth threshold value calculation unit 51 does not depend on the vehicle speed as shown in FIG. 8 as the fourth threshold value. A constant value SV4 (for example, 1.5 m) is calculated. The fourth threshold value calculation unit 51 sets the fourth threshold value to 0 when the image obstacle detection unit 44 has not detected an obstacle approaching the rear of the host vehicle 1.

  When the shift position detection unit 9 detects the reverse position and the image obstacle detection unit 44 detects an obstacle, the threshold value setting unit 52 is constant regardless of the vehicle speed of the host vehicle 1. Of the second threshold value SV2, the third threshold value SV3, or the fourth threshold value SV4.

  On the other hand, when the shift position detection unit 9 does not detect the reverse position, or when the image obstacle detection unit 44 does not detect an obstacle, the threshold setting unit 52 sets the first threshold as the operation threshold. The value SV1 is selected. Thereby, the threshold value setting unit 52 can control the operation threshold value so that the operation threshold value increases as the vehicle speed of the host vehicle 1 increases.

  A case where the operation threshold value is controlled to a constant value (SV2 to SV4) will be described in detail. The threshold value setting unit 52 changes the operation threshold value according to the detection angle regions GDC1, GDC2, GDL, and GDR where the obstacle is detected. Specifically, when an obstacle is detected in the left side detection angle region GDL or the right side detection angle region GDR, the threshold value setting unit 52 uses the second threshold value SV2 (for example, 1.. 5m) is selected. When not detected in the left side detection angle region GDL and the right side detection angle region GDR but detected in the rear detection angle region GDC1 or GDC2, the threshold value setting unit 52 sets the third threshold value SV3 as the operation threshold value. (For example, 1.0 m) is selected. When detected in the left detection angle region GDL and detected in the rear detection angle region GDC1 within a predetermined time (for example, 3 seconds), or detected in the right detection angle region GDR and the rear detection angle region GDC2 Is detected, the threshold value setting unit 52 selects the fourth threshold value SV4 (for example, 1.5 m) as the operation threshold value.

  As described above, when the image obstacle detection unit 44 detects an obstacle in the left side detection angle region GDL or the right side detection angle region GDR, the threshold value setting unit 52 performs the detection in the rear detection angle region GDC1 or GDC2. The operation threshold value is increased as compared with the case where an obstacle is detected. As a result, it is possible to advance the timing of warning when it is detected on the left and right sides compared to when it is detected directly behind, so the timing of the warning is appropriately changed according to the danger level of the obstacle be able to.

  The threshold value setting unit 52 may change the operation threshold value for each of the ultrasonic obstacle detection sensors 13e to 13h according to the detection angle regions GDC1, GDC2, GDL, and GDR where the obstacle is detected.

  The ultrasonic obstacle detection sensor 13e will be described. When the ultrasonic obstacle detection sensor 13e does not detect an obstacle at a predetermined time before the host vehicle 1 starts moving backward, or the distance of the obstacle detected by the ultrasonic obstacle detection sensor 13e is When the distance is changed by a predetermined distance (for example, 0.1 m) or more, the operating threshold value of the ultrasonic obstacle detection sensor 13e is set to the larger one (maximum value) of the first threshold value SV1 and the second threshold value SV2. To do. However, the second threshold value SV2 may be selected only when the image obstacle detection unit 44 detects an obstacle in the left side detection angle region GDL. The ultrasonic obstacle detection sensor 13e detects the obstacle at a predetermined time before the host vehicle 1 starts moving backward, and the obstacle distance detected by the ultrasonic obstacle detection sensor 13e is a predetermined distance. When there is no change (for example, 0.1 m) or when the image obstacle detection unit 44 has not detected an obstacle in the left side detection angle region GDL, the operation threshold value of the ultrasonic obstacle detection sensor 13e The first threshold value SV1 may be selected as If a parked vehicle or curbstone behind the host vehicle 1 is detected as an obstacle, or if the image obstacle detection unit 44 does not detect an obstacle in the left-side detection angle region GDL, The operating threshold value of the sonic obstacle detection sensor 13e can be changed according to the vehicle speed.

  The ultrasonic obstacle detection sensor 13f will be described. When the ultrasonic obstacle detection sensor 13f does not detect an obstacle at a predetermined time before the host vehicle 1 starts moving backward, or the distance of the obstacle detected by the ultrasonic obstacle detection sensor 13f is When the distance is changed by a predetermined distance (for example, 0.1 m) or more, the operation threshold value of the ultrasonic obstacle detection sensor 13f is set to the first threshold value SV1, the second threshold value SV2, the third threshold value SV3, And the maximum value of the fourth threshold value SV4. However, the second threshold value SV2 may be selected only when the image obstacle detection unit 44 detects an obstacle in the left side detection angle region GDL. Only when the image obstacle detection unit 44 detects an obstacle in the rear detection angle region GDC1, the third threshold value SV3 or the fourth threshold value SV4 may be selected. Then, the ultrasonic obstacle detection sensor 13f detects the obstacle at a predetermined time before the vehicle 1 starts moving backward, and the obstacle distance detected by the ultrasonic obstacle detection sensor 13f is a predetermined distance. When it has not changed (for example, 0.1 m) or when the image obstacle detection unit 44 has not detected an obstacle in the rear detection angle region GDC1, the operation threshold value of the ultrasonic obstacle detection sensor 13f is used. The first threshold value SV1 may be selected.

  The ultrasonic obstacle detection sensor 13g will be described. When the ultrasonic obstacle detection sensor 13g has not detected an obstacle at a predetermined time before the host vehicle 1 starts moving backward, or the distance of the obstacle detected by the ultrasonic obstacle detection sensor 13g is When the distance is changed by a predetermined distance (for example, 0.1 m) or more, the operation threshold value of the ultrasonic obstacle detection sensor 13g is set to the first threshold value SV1, the second threshold value SV2, the third threshold value SV3, And the maximum value of the fourth threshold value SV4. However, the second threshold value SV2 may be selected only when the image obstacle detection unit 44 detects an obstacle in the right side detection angle region GDR. Only when the image obstacle detection unit 44 detects an obstacle in the rear detection angle region GDC2, the third threshold value SV3 or the fourth threshold value SV4 may be selected. Then, the ultrasonic obstacle detection sensor 13g detects the obstacle at a predetermined time before the vehicle 1 starts moving backward, and the obstacle distance detected by the ultrasonic obstacle detection sensor 13g is a predetermined distance. When it has not changed (for example, 0.1 m) or when the image obstacle detection unit 44 has not detected an obstacle in the rear detection angle region GDC2, the operation threshold value of the ultrasonic obstacle detection sensor 13g is used. The first threshold value SV1 may be selected.

  The ultrasonic obstacle detection sensor 13h will be described. When the ultrasonic obstacle detection sensor 13h does not detect an obstacle at a predetermined time before the host vehicle 1 starts moving backward, or the distance of the obstacle detected by the ultrasonic obstacle detection sensor 13h is When the distance is changed by a predetermined distance (for example, 0.1 m) or more, the operating threshold value of the ultrasonic obstacle detection sensor 13h is set to the larger one (maximum value) of the first threshold value SV1 and the second threshold value SV2. To do. However, the second threshold value SV2 may be selected only when the image obstacle detection unit 44 detects an obstacle in the right side detection angle region GDR. Then, the ultrasonic obstacle detection sensor 13h detects the obstacle at a predetermined time before the vehicle 1 starts moving backward, and the obstacle distance detected by the ultrasonic obstacle detection sensor 13h is a predetermined distance. When there is no change (for example, 0.1 m) or when the image obstacle detection unit 44 does not detect an obstacle in the right side detection angle region GDR, the operation threshold value of the ultrasonic obstacle detection sensor 13h The first threshold value SV1 may be selected as

  As described above, by changing the operation threshold value for each of the ultrasonic obstacle detection sensors 13e to 13h according to the detection angle regions GDL, GDC1, GDC2, and GDR in which the obstacle is detected, The warning timing can be appropriately changed for each of the ultrasonic obstacle detection sensors 13e to 13h according to the detection direction.

  Further, the threshold value setting unit 52 includes an ultrasonic obstacle detection sensor 13e in which the ultrasonic detection ranges CRL, CNL, CNR, and CRR overlap with the detection angle regions GDL, GDC1, GDC2, and GDR where the obstacle is detected. The operation threshold value of ˜13h may be set larger than the operation threshold value of the ultrasonic obstacle detection sensors 13e to 13h in which the ultrasonic detection ranges CRL, CNL, CNR, and CRR do not overlap. Thereby, the warning timing can be advanced with respect to the obstacle detection direction.

  Furthermore, the second threshold value SV2 may be set to the fourth threshold value SV4 or more, and the fourth threshold value SV4 may be set to the third threshold value SV3 or more. Accordingly, it is determined that an obstacle approaching the host vehicle 1 from the side of the host vehicle 1 is higher in risk than an obstacle approaching the host vehicle 1 from directly behind the host vehicle 1, and the warning timing is advanced. be able to.

  As shown in FIG. 9, when the image obstacle detection unit 44 detects an obstacle OBJ in the left-side detection angle region GDL, the operation thresholds of the ultrasonic obstacle detection sensors 13e (CRL) and 13f (CNL) are detected. A constant value (second to fourth threshold values) that does not depend on the host vehicle speed may be selected as the value.

  As shown in FIG. 10, when the image obstacle detection unit 44 detects the obstacle OBJ in the rear detection angle region GDC1 or GDC2, the ultrasonic obstacle detection sensors 13f (CNL) and 13g (CNR) operate. As the threshold value, a constant value (second to fourth threshold values) independent of the host vehicle speed may be selected.

  As shown in FIG. 11, when the image obstacle detection unit 44 detects the obstacle OBJ in the left side detection angle region GDL and detects the obstacle OBJ in the rear detection angle region GDC1 within a predetermined time, the ultrasonic obstacle As the operation threshold values of the object detection sensors 13f (CNL) and 13g (CNR), a constant value (second to fourth threshold values) independent of the host vehicle speed may be selected. The same applies when the image obstacle detection unit 44 detects the obstacle OBJ in the right side detection angle region GDR and detects the obstacle OBJ in the rear detection angle region GDC2 within the predetermined time.

  The operation threshold values of the selected ultrasonic obstacle detection sensors 13e to 13h are the brake control determination unit 25, the accelerator pedal operation reaction force determination unit 28, the notification determination unit 31, and the driving force control determination unit as warning control units. 34 respectively. The brake control determination unit 25, the accelerator pedal operation reaction force determination unit 28, the notification determination unit 31, and the driving force control determination unit 34 calculate the respective operation thresholds with different weights for each warning control. For example, R1_K1 ≦ R1_K2 ≦ R1_K4 ≦ R1_K3. This enables weighting that operates in the order of notification, driving force control, accelerator pedal operation reaction force control, and braking control.

  The braking control determination unit 25 determines to generate a braking force as an obstacle approach warning when the following condition A01 is satisfied. However, the distance from the obstacle detected by the ultrasonic obstacle detection sensors 13e to 13h is referred to as “ultrasonic sensor detection distance”. The operation threshold value obtained by multiplying the braking control coefficient R1_K1 is defined as a braking operation threshold value.

  A01 Operation threshold for braking> Ultrasonic sensor detection distance

  The brake control unit 26 increases the brake pressure at a predetermined rate of change when the brake control determination unit 25 determines to activate the warning by braking, and maintains the state when the predetermined target brake pressure is reached. When the holding time reaches a predetermined time (for example, 0.8 seconds) or when a predetermined time has elapsed since the vehicle speed = 0, the brake pressure is reduced to 0 at a predetermined change rate. Note that both the predetermined rate of change and the predetermined target brake pressure may be changed according to the vehicle speed or the distance from the obstacle. The braking force generator 27 controls the actual brake pressure for each of the wheels 20a to 20d so that the target brake pressure calculated by the braking control unit 26 is obtained.

  The accelerator pedal operation reaction force determination unit 28 determines that the accelerator pedal operation reaction force is generated as an obstacle approach warning when the following condition A04 is satisfied. However, the operation threshold value obtained by multiplying the accelerator pedal reaction force coefficient R1_K2 is set as the APD operation threshold value.

  A04 Operation threshold for APD> Detection distance of ultrasonic sensor

  When the accelerator pedal operation reaction force control unit 29 determines that the accelerator pedal operation reaction force determination unit 28 generates an accelerator pedal operation reaction force, the accelerator pedal operation reaction force control unit 29 increases the reaction force command value at a predetermined rate of change, thereby increasing the predetermined reaction force command. When the value is reached, keep that state. When the holding time reaches a predetermined time (for example, 0.8 seconds), the reaction force command value is decreased to 0 at a predetermined change rate. Note that both the predetermined change rate and the predetermined reaction force command value may be changed according to the vehicle speed or the distance from the obstacle. The accelerator pedal operation reaction force generator 30 controls the operation reaction force of the accelerator pedal so that the reaction force command value calculated by the accelerator pedal operation reaction force control unit 29 is obtained.

  When the following condition A07 is satisfied, the notification determination unit 31 determines to issue a warning by voice or buzzer as an obstacle approach warning. However, the operation threshold value multiplied by the alarm coefficient R1_K3 is set as the alarm operation threshold value.

  A07 Alarm threshold> Ultrasonic sensor detection distance

  The notification control unit 32 repeats turning on and off of the buzzer driving signal for a predetermined time when the notification determination unit 31 determines that an alarm is issued. The notification device 33 issues an alarm based on the buzzer drive signal calculated by the notification control unit 32. For example, a predetermined tone color “beep” is repeatedly generated. Alternatively, the alarm may continue to sound while the obstacle satisfies the above conditions. Further, simultaneously with the alarm, a light emitting object such as an indicator installed in the meter may be turned on or blinked.

  The driving force control determination unit 34 determines that the driving force control is performed as an obstacle approach warning when the following condition A10 is satisfied. However, the operation threshold value obtained by multiplying the driving force coefficient R1_K4 is set as the driving force operation threshold value.

  A10 Actuation threshold for driving force> Detection distance of ultrasonic sensor

  When the driving force control determination unit 34 determines that the driving force control is to be performed, the driving force control unit 35 increases the reduction amount of the accelerator opening at a predetermined change rate. When the reduction amount of the accelerator opening reaches a predetermined value, the state is maintained. If the reduction amount is maintained for a predetermined time, the reduction amount of the accelerator opening is reduced to zero. The final throttle opening of the engine is a value obtained by subtracting the reduction amount of the accelerator opening calculated by the driving force control unit 35 from the accelerator opening of the driver operation. Note that both the predetermined change rate and the predetermined amount of reduction in the accelerator opening may be changed according to the vehicle speed or the distance from the obstacle. The driving force generator 36 controls the engine output based on the final engine throttle opening calculated by the driving force control unit 35.

  2, the system state selection unit 23, the control determination information calculation unit 24, the brake control determination unit 25, the brake control unit 26, the accelerator pedal operation reaction force determination unit 28, the accelerator pedal operation reaction force control unit 29, and a notification The determination unit 31, the notification control unit 32, the driving force control determination unit 34, and the driving force control unit 35 can be configured as a part of the vehicle control device 2 in FIG. Of course, an arithmetic processing device different from the vehicle control device 2 is prepared, and a CPU in the arithmetic processing device executes a computer program stored in advance. Accordingly, the system state selection unit 23, the control determination information calculation unit 24, the braking control determination unit 25, the braking control unit 26, the accelerator pedal operation reaction force determination unit 28, the accelerator pedal operation reaction force control unit 29, the notification determination unit 31, You may implement | achieve operation | movement of the alerting | reporting control part 32, the driving force control judgment part 34, and the driving force control part 35. FIG.

[Driving control processing]
The control unit of the travel control apparatus having the above-described configuration performs the following travel control process when the host vehicle 1 moves backward, thereby performing the ultrasonic obstacle detection sensors 13e to 13h or the image obstacle detection unit 44. The obstacle detected by can be warned at an appropriate warning timing. Hereinafter, with reference to the flowchart shown in FIG. 12, operation | movement of the traveling control apparatus at the time of performing traveling control processing is demonstrated.

  In the flowchart shown in FIG. 12, the system state selection unit 23 determines that the on / off switch of the travel control device is on, and the shift position detection unit 9 determines that the shift position of the vehicle 1 is R (reverse). The travel control process is started at the timing when it is determined that the vehicle is in the position, and the process proceeds to step S1. The traveling control process is repeatedly executed as long as the on / off switch of the traveling control device is in the on state and the shift position of the vehicle 1 is positioned at the R position. The timing for starting the travel control process is not limited to the above conditions. For example, in addition to the above conditions, conditions such as the vehicle speed being a predetermined value or less and the steering angle being a predetermined value or less may be added.

In the process of step S1, the host vehicle information acquisition unit 21 uses the vehicle speed of the host vehicle 1, the accelerator opening, the position of the brake pedal, the shift position, and the state of the on / off switch of the travel control device as the host vehicle information. The steering angle and acceleration / deceleration are acquired.

  In the process of step S2, the peripheral information acquisition unit 22 acquires the detection results by the ultrasonic obstacle detection sensors 13e to 13h, that is, the presence / absence of the obstacle and the distance from the obstacle. In the process of step S3, the peripheral information acquisition unit 22 acquires the detection result by the image obstacle detection unit 44, that is, the presence or absence of an obstacle. In addition, in step S2 or S3, as surrounding information, presence / absence of obstacles present in the front PD, rear and side of the vehicle 1, distance and relative speed with the obstacle, approach time, and obstacle detection described later The direction or the detection angle may be acquired.

  In step S4, the first threshold value calculation unit 48 to the fourth threshold value calculation unit 51 calculate the first threshold value SV1 to the fourth threshold value SV4, respectively. In step S5, the threshold value setting unit 52 selects any one of the first threshold value SV1, the second threshold value SV2, the third threshold value SV3, and the fourth threshold value SV4 as the operation threshold value. To do.

  In the process of step S6, the braking control determination unit 25, the accelerator pedal operation reaction force determination unit 28, the notification determination unit 31, and the driving force control determination unit 34 calculate the respective operation thresholds by changing the weight for each warning control. To do. Each of the braking control determination unit 25, the accelerator pedal operation reaction force determination unit 28, the notification determination unit 31, and the driving force control determination unit 34 makes an obstacle approach warning according to the above-described conditions A01, A04, A07, and A010. It is determined whether or not to perform.

  Specifically, each calculated operation threshold value is compared with the distance between the obstacle acquired in step S2. When the distance to the obstacle is smaller than the operation threshold (YES in S6), the process proceeds to step S7, where an obstacle approach warning is given. On the other hand, if the distance from the obstacle is equal to or greater than the operating threshold (NO in S6), the warning in FIG.

  With reference to FIG. 13A to FIG. 13C, the change of the operation threshold value SSV according to the detection state of the obstacle by the image obstacle detection unit 44, and the difference between the operation threshold value SSV and the obstacle. The warning determination according to the comparison result of the distance DOD will be described. When no obstacle is detected by the image obstacle detection unit 44, the operation threshold value SSV is equal to the first threshold value regardless of whether the ultrasonic obstacle detection sensors 13e to 13h detect the obstacle. Set to the value SV1. Therefore, the operation threshold value SSV changes according to the host vehicle speed. As time elapses, the distance DOD from the obstacle becomes shorter, and the obstacle is started to be detected by the image obstacle detection unit 44 (time t2). Then, the operating threshold value SSV is a value other than the first threshold value SV1, and is set to any one of the second threshold value SV2 to the fourth threshold value SV4 that is larger than the first threshold value SV1. The At time t3, the distance DOD to the obstacle becomes larger than the operation threshold value SSV, so that it is determined that the warning is performed. When an obstacle is detected by the image obstacle detector 44, the warning timing can be advanced from time t4 to time t3 by changing the operation threshold.

  As described above, according to the embodiment of the present invention, the following effects can be obtained.

  When the shift position detection unit 9 determines that the shift position of the vehicle 1 is in the R (reverse) position and the image obstacle detection unit 44 detects an obstacle, the risk of the obstacle is high. It can be judged. Therefore, in this case, by controlling the operation threshold value to a constant value regardless of the vehicle speed of the host vehicle 1, the warning timing is changed according to the danger level of the obstacle, and the danger level of the obstacle is driven. Can be notified to the person.

  The image obstacle detection unit 44 divides a range including the rear of the host vehicle 1 into a plurality of detection angle regions GDL, GDC1, GDC2, and GDR, and detects an obstacle entering the rear of the host vehicle 1 as a detection angle region GDL, Detection is performed for each of GDC1, GDC2, and GDR. The threshold value setting unit 52 changes the operation threshold value according to the detection angle regions GDL, GDC1, GDC2, and GDR where the obstacle is detected. Thereby, the danger level of an obstacle can be changed according to the detection direction of an obstacle, and the warning timing can be changed according to the danger level of an obstacle.

  The image obstacle detection unit 44 is adjacent to at least the rear detection angle regions GDC1 and GDC2 including the rear of the host vehicle and both sides of the rear detection angle regions GDC1 and GDC2 as a plurality of detection angle regions GDL, GDC1, GDC2, and GDR. The left side detection angle region GDL and the right side detection angle region GDR are divided. When the image obstacle detection unit 44 detects an obstacle in the left side detection angle region GDL or the right side detection angle region GDR, the threshold value setting unit 52 detects the obstacle in the rear detection angle regions GDC1 and GDC2. The operating threshold value is increased compared to the case where As a result, it is possible to advance the timing of warning when it is detected on the left and right sides compared to when it is detected directly behind, so the timing of the warning is appropriately changed according to the danger level of the obstacle be able to.

  In the ultrasonic detection ranges CRL, CNL, CNR, and CRR that are different from each other, a plurality of ultrasonic obstacle detection sensors 13e to 13h that detect the obstacle and the distance from the obstacle are provided. The threshold value setting unit 52 changes the operation threshold value for each of the ultrasonic obstacle detection sensors 13e to 13h according to the detection angle regions GDL, GDC1, GDC2, and GDR where the obstacle is detected. Thereby, the warning timing can be appropriately changed for each of the ultrasonic obstacle detection sensors 13e to 13h according to the detection direction of the obstacle.

  The threshold setting unit 52 includes ultrasonic obstacle detection sensors 13e to 13h in which the ultrasonic detection ranges CRL, CNL, CNR, and CRR overlap with the detection angle regions GDL, GDC1, GDC2, and GDR in which the obstacle is detected. Is made larger than the operation threshold values of the ultrasonic obstacle detection sensors 13e to 13h in which the ultrasonic detection ranges CRL, CNL, CNR, and CRR do not overlap. Thereby, the warning timing can be advanced with respect to the obstacle detection direction.

  When the ultrasonic obstacle detection sensors 13e to 13h have not detected an obstacle at a predetermined time before the host vehicle 1 starts moving backward, or the obstacles detected by the ultrasonic obstacle detection sensors 13e to 13h Only when the distance of the object is changing, the threshold value setting unit 52 controls the operation threshold value to a constant value regardless of the vehicle speed of the host vehicle 1. By controlling the operation threshold value to a constant value only when the obstacle entered after the start of reversal or the obstacle is a moving object, it is possible to adjust the speed of the adjacent parked vehicle or wall according to the vehicle speed. Since the operation threshold value can be controlled, the warning timing can be appropriately changed according to the danger level of the obstacle.

  The entire contents of Japanese Patent Application No. 2012-040284 (filing date: February 27, 2012) are incorporated herein by reference.

  Although the contents of the present invention have been described with reference to the embodiments, the present invention is not limited to these descriptions, and it is obvious to those skilled in the art that various modifications and improvements can be made.

  According to the travel control device and the travel control method according to the present embodiment, the warning timing can be changed in accordance with the danger level of the obstacle to notify the driver of the danger level of the obstacle. Therefore, the present invention has industrial applicability.

9: Shift position detector (rear movement preparation detector)
13e to 13h ... ultrasonic obstacle detection sensor (ultrasonic obstacle detection unit)
25. Braking control determination unit (warning control unit)
26: Braking control unit (warning control unit)
27 ... Brake force generator (warning unit)
28 ... accelerator pedal reaction force determination unit (warning control unit)
29 ... Accelerator pedal reaction force control unit (warning control unit)
30 ... Accelerator pedal operation reaction force generator (warning part)
31 ... Notification determination unit (warning control unit)
32. Notification control unit (warning control unit)
33 ... Notification device (warning unit)
34 ... Driving force control determination unit (warning control unit)
35 ... Driving force control unit (warning control unit)
36 ... Driving force generator (warning section)
38 ... Relative speed estimation unit 44 ... Image obstacle detection unit 46 ... Camera (image acquisition unit)
52 ... Threshold setting unit (threshold control unit)
61 ... Vehicle (obstacle)
CRL, CNL, CNR, CRR ... Ultrasonic detection range GDC1, GDC2 ... Back detection angle region GDL ... Left side detection angle region GDR ... Right side detection angle region OBJ ... Obstacle

Claims (7)

An ultrasonic obstacle detection unit that detects an obstacle approaching the rear of the vehicle and a distance from the obstacle using ultrasonic waves;
An image acquisition unit that acquires an image of a range including the rear of the vehicle;
An image obstacle detection unit that detects an obstacle approaching the rear of the vehicle using the image acquired by the image acquisition unit;
A backward movement preparation detection unit that detects that the own vehicle is moving backward by detecting that the shift position of the transmission of the own vehicle is a reverse position ;
About the obstacle detected by the ultrasonic obstacle detection unit, a warning unit that warns the driver of the vehicle ,
A warning control unit that controls the warning unit to perform the warning when a distance from the obstacle detected by the ultrasonic obstacle detection unit is equal to or less than a warning operation threshold;
The operation threshold value is increased as the vehicle speed increases except when the backward movement preparation detection unit detects the preparation of the vehicle moving backward and the image obstacle detection unit detects an obstacle. A threshold value control unit that controls the operation threshold value according to the vehicle speed of the host vehicle,
When the preparation for moving the vehicle backward is detected by the backward movement preparation detection unit and the image obstacle detection unit detects an obstacle, the threshold control unit sets the operation threshold value. The operation threshold value is controlled to a constant value regardless of the vehicle speed of the host vehicle so that the warning is easily performed as compared with the case where the control is performed according to the vehicle speed of the host vehicle. Control device. The image obstacle detection unit divides a range including the rear of the own vehicle into a plurality of detection angle regions, and detects an obstacle entering the rear of the own vehicle for each detection angle region,
When the backward movement preparation detection unit detects that the vehicle is moving backward, and the image obstacle detection unit detects an obstacle, the threshold control unit detects an obstacle. The travel control device according to claim 1, wherein the operation threshold value is changed according to a detection angle region. The image obstacle detection unit includes, as the plurality of detection angle areas, at least a rear detection angle area including the rear of the host vehicle, a left side detection angle area and a right side detection angle adjacent to both sides of the rear detection angle area, respectively. Divided into areas,
When the image obstacle detection unit detects an obstacle in the left side detection angle region or the right side detection angle region, the threshold value control unit detects an obstacle in the rear detection angle region. The travel control device according to claim 2, wherein the operation threshold value is increased as compared with a case. The ultrasonic obstacle detection unit includes a plurality of ultrasonic obstacle detection sensors that detect an obstacle and a distance from the obstacle in different ultrasonic detection ranges,
The said threshold value control part changes the said operation threshold value for every ultrasonic obstacle detection sensor according to the detection angle area | region where the obstacle was detected. The Claim 2 or Claim 3 characterized by the above-mentioned. The travel control device according to any one of claims.   The threshold control unit is configured such that the ultrasonic detection range overlaps the operating threshold value of the ultrasonic obstacle detection sensor in which the ultrasonic detection range overlaps the detection angle region where the obstacle is detected. The travel control device according to claim 4, wherein the travel control device is larger than the operation threshold value of the ultrasonic obstacle detection sensor.   When the ultrasonic obstacle detecting unit has not detected an obstacle at a predetermined time before the vehicle starts moving backward, or the distance of the obstacle detected by the ultrasonic obstacle detecting unit is Only when the threshold value has changed, the threshold control unit operates the operation threshold so that the warning can be performed more easily than when the operation threshold value is controlled in accordance with the vehicle speed of the host vehicle. The travel control device according to any one of claims 1 to 5, wherein the value is controlled to a constant value regardless of the vehicle speed of the host vehicle. An ultrasonic obstacle detection unit that detects an obstacle approaching the rear of the vehicle and a distance from the obstacle using ultrasonic waves;
An image acquisition unit that acquires an image of a range including the rear of the vehicle;
An image obstacle detection unit that detects an obstacle approaching the rear of the host vehicle using the image acquired by the image acquisition unit;
A backward movement preparation detection unit that detects that the own vehicle is moving backward by detecting that the shift position of the transmission of the own vehicle is a reverse position ;
About the obstacle detected by the ultrasonic obstacle detection unit, a warning control unit that warns the driver of the own vehicle , and a travel control method using a travel control device,
Controlling the warning unit to perform the warning when the distance from the obstacle detected by the ultrasonic obstacle detection unit is equal to or less than a warning operating threshold;
The operation threshold value is increased as the vehicle speed increases except when the backward movement preparation detection unit detects the preparation of the vehicle moving backward and the image obstacle detection unit detects an obstacle. The operating threshold value is controlled according to the vehicle speed of the host vehicle,
When the preparation for moving the vehicle backward is detected by the backward movement preparation detection unit and the image obstacle detection unit detects an obstacle, the operation threshold value is set according to the vehicle speed of the vehicle. The travel control method, wherein the operation threshold value is controlled to a constant value regardless of the vehicle speed of the host vehicle so that the warning is more easily performed than in the case of control.

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